I'd like to disagree. I feel like time and effort needs to be put in to complete these courses. Yeah, the first couple of times you beat it might be sheer luck, but that's how you figure out your path.
During the playground competition thing, it's not like I found my route by creating a 3D map and plotting out the fastest route. It was done by trial, error, and luck. While doing a run, I'd mess up and hit something which turned out to be a better route than the original.
I will say that the donut-ramp start track is very hard to nail, but if you're going for record times, you have to leave some things up to luck. Otherwise you just have to slow down to increase precision.
Edit: To clarify, I spent more than 2 hours on the final Carkour level alone and I can most of it pretty regularly. Maybe not right now since I'm out of practice, but it's less about twitch precision and more about strategy and setup.